Question

Java Programming:

Using textI/O models, create a Write file, Append file, and a Read file. Write 10 fahrenheit temperature to a text file, append 5 more temperatures, then read these numbers calculating, in a method, the Celsius temperature, and printing the results via another method.

Answer 1

// Program in JAVA

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;

class Main
{
//main function
public static void main (String[] args) throws FileNotFoundException, IOException
{
// variables for path of the files
String readFilePath = "C:\\\\Users\\\\shubham\\\\Desktop\\\\Read.txt";
String writeFilePath = "C:\\\\Users\\\\shubham\\\\Desktop\\\\Write.txt";
String appendFilePath = "C:\\\\Users\\\\shubham\\\\Desktop\\\\Append.txt";
  
// create read, write & append files
File readFile = new File(readFilePath);
File writeFile = new File(writeFilePath);
File appendFile = new File(appendFilePath);

// check if files are created and display the prompt accordingly
if (readFile.createNewFile() && writeFile.createNewFile() && appendFile.createNewFile())
{
System.out.println("Files are created!");
}
else
{
System.out.println("One(or more) file(s) already exist!");
}
  
//Write Content read from readFile to writeFile
FileWriter writer = new FileWriter(writeFile);
// store the readFileFun() returned string in a variable
String temp = readFileFun(readFilePath);
// split the string by newline
String lines[] = temp.split("\n");
// write each line to file
int i=0;
while(i!=lines.length)
{
writer.write(lines[i] + "\n");
i++;
}
// close the file
writer.close();
  
//Write Content read from appendFile to writeFile by setting second parameter to true
FileWriter append = new FileWriter(writeFile, true);
// create new printwriter object
PrintWriter pw = new PrintWriter(append);
// append to file using that object
pw.println(readFileFun(appendFilePath));
// close the file
pw.close();
  
//Now read the data from the readfile to display the converted temperature on the screen
String readData = readFileFun(readFilePath);
// split the string by newline
String eachLines[] = readData.split("\n");
i=0;
while(i != eachLines.length)
{
System.out.println("Original temperature(in Fahrenheit): " + eachLines[i]
+ " Converted temperature(in Celsius): " + ((Integer.valueOf(eachLines[i])-32)*5/9));
i++;
}
}
  
// function to readFile from a file with path being provided as a parameter
private static String readFileFun(String pathOfFile)
{
// create a new StringBuilder object to build a string by appending read data
StringBuilder sb = new StringBuilder();
// try reading the file by bufferedreader object
try (BufferedReader br = new BufferedReader(new FileReader(pathOfFile)))
{
// variable to store each line
String line;
while ((line = br.readLine()) != null)
{
// append each line to the stringbuilder object
sb.append(line).append("\n");
}
}
// catch exception if file is not found
catch (IOException e)
{
e.printStackTrace();
}
// return the object as string
return sb.toString();
}
}

// Contents of Read.txt

40
44
88
144
56
75
68
94
55
66

// Contents of Append.txt

65
55.5
77.7
45.6
89.9

// Contents of Write.txt (Note that this may not appear formatted(with newline) in notepad, try better editors for desired formatting)

40
44
88
144
56
75
68
94
55
66
65
55.5
77.7
45.6
89.9

// Output

One(or more) file(s) already exist!
Original temperature(in Fahrenheit): 40 Converted temperature(in Celsius): 4
Original temperature(in Fahrenheit): 44 Converted temperature(in Celsius): 6
Original temperature(in Fahrenheit): 88 Converted temperature(in Celsius): 31
Original temperature(in Fahrenheit): 144 Converted temperature(in Celsius): 62
Original temperature(in Fahrenheit): 56 Converted temperature(in Celsius): 13
Original temperature(in Fahrenheit): 75 Converted temperature(in Celsius): 23
Original temperature(in Fahrenheit): 68 Converted temperature(in Celsius): 20
Original temperature(in Fahrenheit): 94 Converted temperature(in Celsius): 34
Original temperature(in Fahrenheit): 55 Converted temperature(in Celsius): 12
Original temperature(in Fahrenheit): 66 Converted temperature(in Celsius): 18

// Screenshot of Code & Output (for reference to indentation)

(Thank You!!)